Conventional incandescent or LED light wires are commonly used in a variety of indoor and outdoor decorative or ornamental lighting applications. For example, such conventional light wires are used to create festive holiday signs, outline architectural structures such as buildings or harbors, and provide under-car lighting systems. These light wires are also used as emergency lighting aids to increase visibility and communication at night or when conditions, such as power outages, water immersion and smoke caused by fires and chemical fog, render normal ambient lighting insufficient for visibility.
Conventional LED light wires consume less power, exhibit a longer lifespan, are relatively inexpensive to manufacture, and are easier to install when compared to light tubes using incandescent light bulbs. Increasingly, LED light wires are used as viable replacements for neon light tubing.
As illustrated in FIG. 1, conventional light wire 100 consists of a plurality of illuminant devices 102, such as incandescent light bulbs or LEDs, connected together by a flexible wire 101 and encapsulated in a protective tube 103. A power source 105 creates an electrical current that flows through the flexible wire 101 causing the illuminant devices 102 to illuminate and create an effect of an illuminated wire. The illuminant devices 102 are connected in series, parallel, or in combination thereof. Also, the illuminant devices 102 are connected with control electronics in such a way that individual illuminant devices 102 may be selectively switched on or off to create a combination of light patterns, such as strobe, flash, chase, or pulse.
In conventional light wires, the protective tube 103 is traditionally a hollow, transparent or semi-transparent tube which houses the internal circuitry (e.g., illuminant devices 102; flexible wire 101). Since there is an air gap between the protective tube 103 and internal circuitry, the protective tube 103 provides little protection for the light wire against mechanical damage due to excessive loads, such as the weight of machinery that is directly applied to the light wire. Furthermore, the protective tube 103 does not sufficiently protect the internal circuitry from environmental hazards, such as water and dust. As a result, these conventional light wires 100 with protective tube 103 are found unsuitable for outdoor use, especially when the light wires are exposed to extreme weather and/or mechanical abuse.
In conventional light wires, wires, such as flexible wire 101, are used to connect the illuminant devices 102 together. In terms of manufacturing, these light wires are traditionally pre-assembled using soldering or crimp methods and then encapsulated via a conventional sheet or hard lamination process in protective tube 103. Such manufacturing processes are labor intensive and unreliable. Furthermore, such processes decrease the flexibility of the light wire.
In response to the above-mentioned limitations associated with conventional light wires and the manufacture thereof, LED light strips have been developed with increased complexity and protection. These LED light strips consist of circuitry including a plurality of LEDs mounted on a support substrate containing a printed circuit and connected to two separate electrical conductors or bus elements. The LED circuitry and the electrical conductors are encapsulated in a protective encapsulant without internal voids (which includes gas bubbles) or impurities, and are connected to a power source. These LED light strips are manufactured by an automated system that includes a complex LED circuit assembly process and a soft lamination process. Examples of these LED light strips and the manufacture thereof are discussed in U.S. Pat. Nos. 5,848,837, 5,927,845 and 6,673,292, all entitled “Integrally Formed Linear Light Strip With Light Emitting Diode”; U.S. Pat. No. 6,113,248, entitled “Automated System For Manufacturing An LED Light Strip Having An Integrally Formed Connected”; and U.S. Pat. No. 6,673,277, entitled “Method of Manufacturing a Light Guide”.
Although these LED light strips are better protected from mechanical damage and environmental hazards, these LED light strips only provide one-way light direction, and are limited to two separate bus elements in its internal LED circuitry. Also, the manufacturing of such LED light strips remains expensive and time-consuming since these LED light strips at least require a protective encapsulant free of internal voids and impurities, as well as crimping each LED connector pin to the internal LED circuitry. Further, the lamination process makes these LED light strips too rigid to bend.